Trouble Brewing on the South Side?

After a rough stretch, Lucas Giolito is coming off of two great starts and is set for a matchup on Friday night with a Tigers team that has mostly been an offensive doormat for much of 2022. And since the mission statement here at NotBurt Inc. includes many mentions of setting ourselves up for success, clearly, now is the perfect time to question his performance going forward. Because where’s the fun without an added degree of difficulty?

As mentioned, Giolito has gotten back on track in his past two starts, allowing a total of 3 ER in back-to-back six-inning outings versus the Angels and Giants, after getting bludgeoned by Toronto and Houston in his previous two starts for 15 ER over 10 IP. His monthly splits certainly tell us that his ERA is going the wrong way (April: 2.57 ERA, May: 4.13 ERA, June+: 6.55 ERA) but those arbitrary endpoints fail to tell the whole story.

For one, everything is tilted so heavily toward the 15 ER in two starts and you don’t want to take too much away from what might’ve just been two really bad nights against two really good, quick-strike offenses. And for two, he also got shelled on May 31, so we could easily shift the numbers even further by changing an endpoint by just a day.

So, to get more specific than a bad month, what Giolito really had was a bad three weeks, posting a 9.47 ERA (7.12 FIP) over a five-start stretch, while running an 8.7 K/9, 3.9 BB/9, and 3.2 HR/9:

The opponent quality is notable, as three games against Toronto and Houston are going to be tough sledding for most pitchers. This, combined with his two most recent excellent starts against the Angels and Giants, should lead us to believe that Giolito’s three-week hiccup was more a function of schedule than internal struggle, right? But opponent quality goes both ways and the Texas and Tampa Bay offenses vs RHP are also worse than you’re assuming. And the same goes for Los Angeles (who are mostly inept outside of Trout/Ohtani) and San Francisco (who’ve been mediocre, at best).

Here are the team ranks for Giolito’s last seven opponents in wOBA, xwOBA, and K% vs RHP since the start of 2022, broken into season-long, since the start of May, and since the start of June:

But let’s put opponents aside, as the more concerning thing is the monthly drip-down that Giolito has suffered in multiple key categories. There is some good news in that his walk rate has ticked down each month, though his current 8.9% BB% is still up nearly two points from his rate from 2021. But when looking at his ratios and strikeout-adjacent metrics, things just keep moving on down:

But that’s also doing some cherry-picking, at least in regards to the ratios, right? We’ll get back to the whiff dips in a minute but it’s easy to say that the rising ratios are being driven, at least in part, by an increase in batted ball luck. Giolito is currently running a .349 BABIP in 2022 that has stayed nearly static by the month and is way up from a .270 BABIP in 2021 and the .263 BABIP that he had for his career prior to entering this season.

So, we’re done, yeah? Giolito’s 27.3% K% is only down slightly from 2021 and his ratios have gotten crushed recently by a combination of some bad luck with scheduling and batted balls. Done and done <insert dusting off hands gif>.

But just one second, mes amies. Sure, Giolito’s BABIP is running high compared to what he’s done recently but you also don’t get to own your previous BABIP forever. And while his BABIP has risen, so have the expected stats against him, implying an increase in the number of balls hit at better angles and higher exit velocities.

Not to oversimplify things but should we be surprised when better hit balls result in more “luck” for batters? Because the above shows a lot more damage being done, and not just on the expected front. Batter’s have posted 75-point increases in wOBA and xwOBA compared to in 2021, with wOBA/xwOBA on contact and SLG/xSLG each increasing by over 100 points. Those aren’t small bumps, they are significant jumps that show batters doing oodles more damage when making contact. And those bumps have been there all season, not just over a bad stretch.

The increased smackage that batters have laid on Giolito would be a lot more tolerable if he was still running the 33% K% that he posted during his initial breakout in 2019-2020 but that elite rate already left last year and hasn’t yet returned in 2022. And while a 27.3% K% isn’t bad by any stretch (and is only down just a bit from last season), the fantasy domino effect is multiplied when taken with the ratio hit he’s suffered from batters doing more damage on contact.

But much like everything else we’ve looked at, Giolito’s whiffiness has dropped more precipitously than is implied by his minor drop in K% from 2021 to 2022. Whether K%, CSW%, SwStr%, Whiff%, or Chase% – if it’s related to strikeouts, Giolito has probably gotten worse every month since last season:

If we pull in closer, the biggest drop in SwStr% is coming from Giolito’s slider (which has dropped from 20.1% SwStr% in 2021 to 15.1% SwStr% in 2022) and the four-seamer, which, at 11.4% SwStr% is only down slightly from an 11.8% SwStr% in 2021 but was down to 10.4% in May and 9.7% since the start of June. These are also the two pitches that have seen the biggest decreases in movement compared to 2021 – probably a total coincidence.

But just to play devil’s advocate on different movements perhaps being behind different results, Giolito’s four-seamer is down about a tick in velocity and 187 RPM, with the rise decreasing by an inch compared to 2021. And in addition to less rise, it’s also getting significantly less horizontal wiggle, with the average break dropping from 6.7 inches to 4.4 inches. Only 2+ inches but that is enough to take Giolito’s heater from 6% above average in 2021 to 25% below average in 2022.

Less velocity, less rise, and a lot more straight? Is it any wonder that batters have posted a .430 wOBA on contact (.476 xwOBAcon) and .628 SLG (.718 xSLG) against it in 2022 which is up from a .380 wOBAcon (.397 xwOBAcon) and .570 SLG (.602 xSLG) in 2021?

For further illustration, below are the heat maps for contact made against Giolito’s four-seamer in 2021 and 2022. Note that when batters made contact in 2021, it was on pitches more distributed around the zone. But in 2022, contact has been more focused in the heart:

The slider, on the other hand, is averaging more horizontal break (2.7 inches to 3.9 inches) but part of that can be attributed to the natural consequences of throwing it slightly slower (85.6 mph to 84.6 mph). And compared to sliders thrown at similar speed/extension, the relative break has stayed mostly static (-1.8 inches vs AVG).

The amount of depth, however, has increased significantly, averaging 37.0 inches of vertical break in 2022 which is up from 32.4 inches in 2021, taking it from -3.0 inches vs AVG to +0.4 inches vs AVG. But more movement doesn’t always equal more success and Giolito has gone from varying how he attacks with the slider to living in the same plane in 2022:

But even with more vertical drop, 2022’s slider has brought with it a serious increase in the damage done against it. Batters have posted a .710 SLG (.648 xSLG) and .452 wOBAcon (.414 xwOBAcon) against it in 2022, compared to a .500 SLG (.472 xSLG) and .309 wOBAcon (.321 xwOBAcon) in 2021.

And just like his four-seamer, where batters are making contact with his slider has also shifted considerably:

To recap:

Four-Seamer

• less velocity, less spin, less rise, less break, fewer whiffs
• more contact in the heart of the zone with oodles more damage done against it

Slider

• less velocity, more drop, fewer whiffs
• more contact in the heart of the zone with oodles* more damage done against it

*That’s now three uses of “oodles” in the same article involving nerdy baseball analysis, which has to be some sort of (important) record.

Besides the actual violence they commit against the pair, the more comfortable batters continue to be with handling Giolito’s four-seamer/slider, the easier it will be to continue laying off of his primo changeup. Batters posted a -11 Run Value (3rd-best among qualified starters) and a -1.1 RV per 100 pitches against Giolito’s changeup in 2021 but that has increased to a +4 RV and +1.3 RV/100 in 2022.

But more importantly, the less often that batters mess with Giolito’s changeup, the less often I’ll get to see batters abused by a pitch that quite literally looks like it rolls off of a table. And that makes me a sa-aad Nicklaus.

Hey Yasmani, pick that thing up!

I’m not saying that Giolito is broken and I’m generally loathed to make sweeping conclusions about an established pitcher that has just gone through a rough stretch. But two of his main pitches are being thrown differently and batters are doing much more damage done against them. And his overall underlying metrics have gotten worse compared to last season, and are getting worse by the month this season. These aren’t judgments, just facts.

They’re important facts, too, in regards to Giolito’s fantasy value for the rest of the season and going forward next year because middling ratios and a strikeout rate that’s above average but not elite, does not a fantasy star make. And if things don’t start ticking back up soon, I have a hard time keeping his value around the same clump of starters that have been his fantasy peers these past few seasons. Especially on a White Sox team that continues to go nowhere fast.

But the most important fact of all is that heading into a Friday night matchup with a Detroit Tigers offense that is 29th in wOBA, 29th in xwOBA, 29th in K%, and 28th in BB% vs RHP, I’ve pretty much guaranteed that Giolito will throw the second no-hitter of his career.

You’re welcome.